Heterogeneity of avenin, the oat prolamin. Fractionation, molecular weight and amino acid composition.

The prolamin, avenin, was extracted from oat seeds and shown to be maximally extractable in 45% (w/w) ethanol. A purification procedure is described and some properties of avenin are examined. As with wheat and barley prolamins, salt soluble and glutelin fractions were simultaneously extracted. Starch gel electrophoresis revealed two novel fractions, which were isolated by ion-exchange chromatography. These fractions have similar amino acid composition, threonine as the N-terminal amino acid and both have a 22 500 molecular weight. It is suggested that the avenin constituents have a common ancestral gene.